1. Field of the Invention
This invention relates to the non-operative or orthotic treatment of scoliosis, lordosis and kyphosis, and more particularly relates to the application of elastic forces to provide a dynamic orthotic device to treat scoliotic, lordotic and kyphotic conditions of the spinal column.
2. Description of the Prior Art
Heretofore, there have been various types of orthoses utilized in the treatment of scoliosis, lordosis, kyphosis, and other abnormal curvatures of the spine. However, these orthoses have been limited almost exclusively to static orthoses as opposed to dynamic orthoses which utilize elastic materials to generate dynamic external forces.
Static orthotic devices can be categorized as supportive, corrective or active corrective orthoses. The supportive types are used as a preventive measure to maintain the present status of a noncorrectable condition and to try to stop the condition from becoming more severe.
The corrective types are basically cylindrical forms that are shaped to as normal, or symmetric, a contour as the abnormal curvature allows. These devices usually completely encompass all portions of the trunk affected by the curvature. The effectiveness of this second category of devices is dependent upon the degree of suppleness or elasticity within the curvature which makes it possible to pre-position or realign an asymmetric spine and trunk into a more normal posture in order to match the symmetric contours of the device. The force to pre-position the trunk is generated by the patient's own muscularture as he puts on the device or is assisted into the device by another person.
The active corrective types of orthoses usually utilize a metal frame which is mounted upon an intimately fitting pelvic portion commonly referred to as the girdle. The frame portion usually extends the length of the spinal column and does not fit the trunk intimately. The frame's rigid structure is used for the attachment of various adjustable pressure pads by means of strapping. The space between the trunk and the surrounding frame allows for manipulation of the curvature by the elective positioning of various kinds of pressure pads to induce a reduction or correction of the curvature. The principal function of the pressure pads is to serve as a reminder to the wearer not to slump against the pads. Thus, the wearer must voluntarily and consciously use his trunk musculature to pull away from the pads thus actively correcting his curvature. Therefore, the amount of time during which the wearer responds to the device to actively correct the curvature is negligible compared to the amount of time that the device acts merely to maintain the status quo of his curvature.
In addition, since the voluntary motion of the spinal column by the wearer must be a conscious act, it follows that during sleep voluntary correction is not possible with a static orthotic device. Furthermore, it is not physically possible to voluntarily produce true corrective derotation in the transverse plane, because there is no physical way for the wearer to differentially rotate the individual vertebrae at will with the varying degree that is required for correction of a particular curvature.
The use of elastic materials as a source of external power can be useful in the development of a practical dynamic orthotic system for the correction of various deformities of the spine. Elastic materials can store and deliver significant amounts of dependable energy. They can be made to produce a continuous force that can be employed in a manner that creates an orthotic system with dynamic forces. The fact that these dynamic forces can be varied in magnitude and made to serve a variety of purposes allows a versatility that far exceeds that of static orthotic systems.
A dynamic orthotic device utilizing elastic materials as a source of external power can produce dynamic forces which are operative while the wearer is awake or asleep. This is important because when the wearer is asleep, the soft tissue surrounding the spinal column is in a relaxed state and the contracted tissue can yield to long-term dynamic pressure accurately directed to the immediate vicinity of the apex of curvature. However, at the same time the vertebral column must be held under firm control in order to prevent diffusion of the force in the form of unwanted lateral shifting of the column as a whole. By using this combination of dynamic pressure and firm control the reduction of the angle of the curvature at the site of the apex results in the overall elongation of the spinal column rather than lateral displacement. Furthermore, by providing the dynamic orthotic device with an adjustable mechanism, it is possible to adjust the device to maintain the correction attained during sleep.
Accordingly, the primary objective of this invention is to provide an efficient, automatic and practical dynamic orthotic system for the treatment of abnormal curvatures of the spine through the application of dynamic external forces generated by elastic materials.
Another objective is to provide a practical dynamic orthotic device which provides dynamic forces which are operative while the wearer is asleep, thereby achieving correction without conscious effort while the soft tissue surrounding the spinal column is in a relaxed state and can more easily yield to dynamic pressure.
Yet another objective is to provide a dynamic orthotic device whereby the dynamic force is applied to the immediate area about the apex of the curvature while holding the rest of the vertebral column under firm control in order to prevent diffusion of the force in the form of unwanted lateral shifting of the spinal column as a whole.
It is also an objective to provide a dynamic orthotic device wherein the external dynamic force also can be applied so as to effectuate a moment to derotate the abnormal transverse rotation that often occurs along with an abnormal curvature of the spine.
A related objective is to provide a dynamic orthotic device whereby the reduction of the angle of the curvature results in an overall elongation of the spinal column and not in lateral displacement.
A further objective is to provide a dynamic orthotic device which is adjustable in a manner which permits the overall mediolateral width of the unit to be gradually drawn in to maintain during the day the correction attained while the wearer was asleep.
A still further objective is to provide a dynamic orthotic device wherein the dynamic forces within the system are readily adjustable in order to facilitate correction of the curvature throughout the continuing long-term corrective process.